Service-orientated architecture is a very popular approach for building large scale, modular and distributed systems as well as achieving integration in heterogeneous environments. Its acceptance in the world of business is growing over time, mainly in technologically advanced countries, but there are still research gaps regarding SOA adoption and diffusion process. Interesting research questions include which factors drive SOA adoption, e.g. whether it is related to specific attributes of organizations. In this research-in-progress paper, we present a research model for identifying and validating the factors affecting SOA adoption in business contexts. Our model takes into consideration both theoretical background regarding factors of impact on IT innovations adoption and factors closely related to specific SOA characteristics. Our research is at a preliminary stage and thus we also present, the research methodology we intend to follow, in order to come up with results and confirm hypotheses.